Initiation of the phosphoinositide cycle by parathyroid hormone in synaptosomes.
We studied the effects of parathyroid hormone 10(-9) M) on the contents of mono-, di-, and triglycerides, total phospholipids, and free arachidonic acid in rat brain cortex synaptosomes using [1-(14)C]arachidonic acid at 2, 5, and 10 sec after addition of the hormone. Our data demonstrated the changes in lipid metabolism in synaptosomal membranes which were especially pronounced at 5 sec after addition of parathyroid hormone. Incorporation of 70% of [1-(14)C]arachidonic acid into the phosphoinositide fraction and the progress of changes in lipid metabolite composition suggest that the phosphoinositide cycle is initiated by parathyroid hormone, and the hormonal signal may be subsequently mediated in nerve cells by 1,2-diacylglycerol, a product of the phosphoinositide cycle.
Khudaverdyan
D N
DN
Geratsi Yerevan State Medical University, Republic of Armenia.
Ter-Markosian
A S
AS
Tadevosyan YuV
D000818:Animals; D004837:Epinephrine / Q000008:administration & dosage / Q000494:pharmacology; D008297:Male; D008858:Microscopy, Phase-Contrast; D008930:Mitochondria, Liver / Q000378:metabolism* / Q000648:ultrastructure; D010101:Oxygen Consumption / Q000187:drug effects*; D010766:Phosphorylation / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013481:Superoxides / Q000494:pharmacology*
D013481:Superoxides; D004837:Epinephrine